diff --git a/src/lib.rs b/src/lib.rs
index 5402b24f7..c88ed73ff 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -26,6 +26,7 @@
 #![cfg_attr(feature = "exts", feature(allocator_api, alloc_layout_extra))]
 #![feature(optin_builtin_traits)]
 #![feature(try_trait)]
+#![feature(abi_efiapi)]
 #![no_std]
 // Enable some additional warnings and lints.
 #![warn(missing_docs, unused)]
diff --git a/src/proto/console/gop.rs b/src/proto/console/gop.rs
index 946714f78..62fd14bf2 100644
--- a/src/proto/console/gop.rs
+++ b/src/proto/console/gop.rs
@@ -37,16 +37,16 @@ use core::ptr;
 #[unsafe_guid("9042a9de-23dc-4a38-96fb-7aded080516a")]
 #[derive(Protocol)]
 pub struct GraphicsOutput<'boot> {
-    query_mode: extern "win64" fn(
+    query_mode: extern "efiapi" fn(
         &GraphicsOutput,
         mode: u32,
         info_sz: &mut usize,
         &mut *const ModeInfo,
     ) -> Status,
-    set_mode: extern "win64" fn(&mut GraphicsOutput, mode: u32) -> Status,
+    set_mode: extern "efiapi" fn(&mut GraphicsOutput, mode: u32) -> Status,
     // Clippy correctly complains that this is too complicated, but we can't change the spec.
     #[allow(clippy::type_complexity)]
-    blt: unsafe extern "win64" fn(
+    blt: unsafe extern "efiapi" fn(
         this: &mut GraphicsOutput,
         buffer: *mut BltPixel,
         op: u32,
diff --git a/src/proto/console/pointer/mod.rs b/src/proto/console/pointer/mod.rs
index be40ca1d7..9380d3157 100644
--- a/src/proto/console/pointer/mod.rs
+++ b/src/proto/console/pointer/mod.rs
@@ -9,8 +9,8 @@ use core::mem::MaybeUninit;
 #[unsafe_guid("31878c87-0b75-11d5-9a4f-0090273fc14d")]
 #[derive(Protocol)]
 pub struct Pointer<'boot> {
-    reset: extern "win64" fn(this: &mut Pointer, ext_verif: bool) -> Status,
-    get_state: extern "win64" fn(this: &Pointer, state: *mut PointerState) -> Status,
+    reset: extern "efiapi" fn(this: &mut Pointer, ext_verif: bool) -> Status,
+    get_state: extern "efiapi" fn(this: &Pointer, state: *mut PointerState) -> Status,
     wait_for_input: Event,
     mode: &'boot PointerMode,
 }
diff --git a/src/proto/console/serial.rs b/src/proto/console/serial.rs
index 460033a6d..c56e6fd8d 100644
--- a/src/proto/console/serial.rs
+++ b/src/proto/console/serial.rs
@@ -18,8 +18,8 @@ pub struct Serial<'boot> {
     // Revision of this protocol, only 1.0 is currently defined.
     // Future versions will be backwards compatible.
     revision: u32,
-    reset: extern "win64" fn(&mut Serial) -> Status,
-    set_attributes: extern "win64" fn(
+    reset: extern "efiapi" fn(&mut Serial) -> Status,
+    set_attributes: extern "efiapi" fn(
         &Serial,
         baud_rate: u64,
         receive_fifo_depth: u32,
@@ -28,10 +28,10 @@ pub struct Serial<'boot> {
         data_bits: u8,
         stop_bits_type: StopBits,
     ) -> Status,
-    set_control_bits: extern "win64" fn(&mut Serial, ControlBits) -> Status,
-    get_control_bits: extern "win64" fn(&Serial, &mut ControlBits) -> Status,
-    write: unsafe extern "win64" fn(&mut Serial, &mut usize, *const u8) -> Status,
-    read: unsafe extern "win64" fn(&mut Serial, &mut usize, *mut u8) -> Status,
+    set_control_bits: extern "efiapi" fn(&mut Serial, ControlBits) -> Status,
+    get_control_bits: extern "efiapi" fn(&Serial, &mut ControlBits) -> Status,
+    write: unsafe extern "efiapi" fn(&mut Serial, &mut usize, *const u8) -> Status,
+    read: unsafe extern "efiapi" fn(&mut Serial, &mut usize, *mut u8) -> Status,
     io_mode: &'boot IoMode,
 }
 
diff --git a/src/proto/console/text/input.rs b/src/proto/console/text/input.rs
index fbfcd5a96..e2d28f54a 100644
--- a/src/proto/console/text/input.rs
+++ b/src/proto/console/text/input.rs
@@ -7,8 +7,8 @@ use core::mem::MaybeUninit;
 #[unsafe_guid("387477c1-69c7-11d2-8e39-00a0c969723b")]
 #[derive(Protocol)]
 pub struct Input {
-    reset: extern "win64" fn(this: &mut Input, extended: bool) -> Status,
-    read_key_stroke: extern "win64" fn(this: &mut Input, key: *mut RawKey) -> Status,
+    reset: extern "efiapi" fn(this: &mut Input, extended: bool) -> Status,
+    read_key_stroke: extern "efiapi" fn(this: &mut Input, key: *mut RawKey) -> Status,
     wait_for_key: Event,
 }
 
diff --git a/src/proto/console/text/output.rs b/src/proto/console/text/output.rs
index be5663ccf..c99646748 100644
--- a/src/proto/console/text/output.rs
+++ b/src/proto/console/text/output.rs
@@ -11,20 +11,20 @@ use core::fmt;
 #[unsafe_guid("387477c2-69c7-11d2-8e39-00a0c969723b")]
 #[derive(Protocol)]
 pub struct Output<'boot> {
-    reset: extern "win64" fn(this: &Output, extended: bool) -> Status,
-    output_string: unsafe extern "win64" fn(this: &Output, string: *const Char16) -> Status,
-    test_string: unsafe extern "win64" fn(this: &Output, string: *const Char16) -> Status,
-    query_mode: extern "win64" fn(
+    reset: extern "efiapi" fn(this: &Output, extended: bool) -> Status,
+    output_string: unsafe extern "efiapi" fn(this: &Output, string: *const Char16) -> Status,
+    test_string: unsafe extern "efiapi" fn(this: &Output, string: *const Char16) -> Status,
+    query_mode: extern "efiapi" fn(
         this: &Output,
         mode: usize,
         columns: &mut usize,
         rows: &mut usize,
     ) -> Status,
-    set_mode: extern "win64" fn(this: &mut Output, mode: usize) -> Status,
-    set_attribute: extern "win64" fn(this: &mut Output, attribute: usize) -> Status,
-    clear_screen: extern "win64" fn(this: &mut Output) -> Status,
-    set_cursor_position: extern "win64" fn(this: &mut Output, column: usize, row: usize) -> Status,
-    enable_cursor: extern "win64" fn(this: &mut Output, visible: bool) -> Status,
+    set_mode: extern "efiapi" fn(this: &mut Output, mode: usize) -> Status,
+    set_attribute: extern "efiapi" fn(this: &mut Output, attribute: usize) -> Status,
+    clear_screen: extern "efiapi" fn(this: &mut Output) -> Status,
+    set_cursor_position: extern "efiapi" fn(this: &mut Output, column: usize, row: usize) -> Status,
+    enable_cursor: extern "efiapi" fn(this: &mut Output, visible: bool) -> Status,
     data: &'boot OutputData,
 }
 
diff --git a/src/proto/media/file/mod.rs b/src/proto/media/file/mod.rs
index 26d5199c2..364b7d231 100644
--- a/src/proto/media/file/mod.rs
+++ b/src/proto/media/file/mod.rs
@@ -271,40 +271,40 @@ impl Drop for FileHandle {
 #[repr(C)]
 pub(super) struct FileImpl {
     revision: u64,
-    open: unsafe extern "win64" fn(
+    open: unsafe extern "efiapi" fn(
         this: &mut FileImpl,
         new_handle: &mut *mut FileImpl,
         filename: *const Char16,
         open_mode: FileMode,
         attributes: FileAttribute,
     ) -> Status,
-    close: extern "win64" fn(this: &mut FileImpl) -> Status,
-    delete: extern "win64" fn(this: &mut FileImpl) -> Status,
-    read: unsafe extern "win64" fn(
+    close: extern "efiapi" fn(this: &mut FileImpl) -> Status,
+    delete: extern "efiapi" fn(this: &mut FileImpl) -> Status,
+    read: unsafe extern "efiapi" fn(
         this: &mut FileImpl,
         buffer_size: &mut usize,
         buffer: *mut u8,
     ) -> Status,
-    write: unsafe extern "win64" fn(
+    write: unsafe extern "efiapi" fn(
         this: &mut FileImpl,
         buffer_size: &mut usize,
         buffer: *const u8,
     ) -> Status,
-    get_position: extern "win64" fn(this: &mut FileImpl, position: &mut u64) -> Status,
-    set_position: extern "win64" fn(this: &mut FileImpl, position: u64) -> Status,
-    get_info: unsafe extern "win64" fn(
+    get_position: extern "efiapi" fn(this: &mut FileImpl, position: &mut u64) -> Status,
+    set_position: extern "efiapi" fn(this: &mut FileImpl, position: u64) -> Status,
+    get_info: unsafe extern "efiapi" fn(
         this: &mut FileImpl,
         information_type: &Guid,
         buffer_size: &mut usize,
         buffer: *mut u8,
     ) -> Status,
-    set_info: unsafe extern "win64" fn(
+    set_info: unsafe extern "efiapi" fn(
         this: &mut FileImpl,
         information_type: &Guid,
         buffer_size: usize,
         buffer: *const c_void,
     ) -> Status,
-    flush: extern "win64" fn(this: &mut FileImpl) -> Status,
+    flush: extern "efiapi" fn(this: &mut FileImpl) -> Status,
 }
 
 /// Disambiguates the file type. Returned by `File::into_type()`.
diff --git a/src/proto/media/fs.rs b/src/proto/media/fs.rs
index 083104910..afb60e2bd 100644
--- a/src/proto/media/fs.rs
+++ b/src/proto/media/fs.rs
@@ -14,7 +14,7 @@ use core::ptr;
 #[derive(Protocol)]
 pub struct SimpleFileSystem {
     revision: u64,
-    open_volume: extern "win64" fn(this: &mut SimpleFileSystem, root: &mut *mut FileImpl) -> Status,
+    open_volume: extern "efiapi" fn(this: &mut SimpleFileSystem, root: &mut *mut FileImpl) -> Status,
 }
 
 impl SimpleFileSystem {
diff --git a/src/proto/pi/mp.rs b/src/proto/pi/mp.rs
index 53528ed5a..27e4fbc76 100644
--- a/src/proto/pi/mp.rs
+++ b/src/proto/pi/mp.rs
@@ -20,7 +20,7 @@ use core::ptr;
 use core::time::Duration;
 
 /// Callback to be called on the AP.
-pub type Procedure = extern "win64" fn(*mut c_void);
+pub type Procedure = extern "efiapi" fn(*mut c_void);
 
 bitflags! {
     /// Flags indicating if the processor is BSP or AP,
@@ -94,17 +94,17 @@ pub struct CPUPhysicalLocation {
 #[unsafe_guid("3fdda605-a76e-4f46-ad29-12f4531b3d08")]
 #[derive(Protocol)]
 pub struct MPServices {
-    get_number_of_processors: extern "win64" fn(
+    get_number_of_processors: extern "efiapi" fn(
         this: *const MPServices,
         number_of_processors: *mut usize,
         number_of_enabled_processors: *mut usize,
     ) -> Status,
-    get_processor_info: extern "win64" fn(
+    get_processor_info: extern "efiapi" fn(
         this: *const MPServices,
         processor_number: usize,
         processor_info_buffer: *mut ProcessorInformation,
     ) -> Status,
-    startup_all_aps: extern "win64" fn(
+    startup_all_aps: extern "efiapi" fn(
         this: *const MPServices,
         procedure: Procedure,
         single_thread: bool,
@@ -113,7 +113,7 @@ pub struct MPServices {
         procedure_argument: *mut c_void,
         failed_cpu_list: *mut *mut usize,
     ) -> Status,
-    startup_this_ap: extern "win64" fn(
+    startup_this_ap: extern "efiapi" fn(
         this: *const MPServices,
         procedure: Procedure,
         processor_number: usize,
@@ -122,18 +122,18 @@ pub struct MPServices {
         procedure_argument: *mut c_void,
         finished: *mut bool,
     ) -> Status,
-    switch_bsp: extern "win64" fn(
+    switch_bsp: extern "efiapi" fn(
         this: *const MPServices,
         processor_number: usize,
         enable_old_bsp: bool,
     ) -> Status,
-    enable_disable_ap: extern "win64" fn(
+    enable_disable_ap: extern "efiapi" fn(
         this: *const MPServices,
         processor_number: usize,
         enable_ap: bool,
         health_flag: *const u32,
     ) -> Status,
-    who_am_i: extern "win64" fn(this: *const MPServices, processor_number: *mut usize) -> Status,
+    who_am_i: extern "efiapi" fn(this: *const MPServices, processor_number: *mut usize) -> Status,
 }
 
 impl MPServices {
diff --git a/src/table/boot.rs b/src/table/boot.rs
index c8f270ea2..9b2203902 100644
--- a/src/table/boot.rs
+++ b/src/table/boot.rs
@@ -18,18 +18,18 @@ pub struct BootServices {
     header: Header,
 
     // Task Priority services
-    raise_tpl: unsafe extern "win64" fn(new_tpl: Tpl) -> Tpl,
-    restore_tpl: unsafe extern "win64" fn(old_tpl: Tpl),
+    raise_tpl: unsafe extern "efiapi" fn(new_tpl: Tpl) -> Tpl,
+    restore_tpl: unsafe extern "efiapi" fn(old_tpl: Tpl),
 
     // Memory allocation functions
-    allocate_pages: extern "win64" fn(
+    allocate_pages: extern "efiapi" fn(
         alloc_ty: u32,
         mem_ty: MemoryType,
         count: usize,
         addr: &mut u64,
     ) -> Status,
-    free_pages: extern "win64" fn(addr: u64, pages: usize) -> Status,
-    get_memory_map: unsafe extern "win64" fn(
+    free_pages: extern "efiapi" fn(addr: u64, pages: usize) -> Status,
+    get_memory_map: unsafe extern "efiapi" fn(
         size: &mut usize,
         map: *mut MemoryDescriptor,
         key: &mut MemoryMapKey,
@@ -37,11 +37,11 @@ pub struct BootServices {
         desc_version: &mut u32,
     ) -> Status,
     allocate_pool:
-        extern "win64" fn(pool_type: MemoryType, size: usize, buffer: &mut *mut u8) -> Status,
-    free_pool: extern "win64" fn(buffer: *mut u8) -> Status,
+        extern "efiapi" fn(pool_type: MemoryType, size: usize, buffer: &mut *mut u8) -> Status,
+    free_pool: extern "efiapi" fn(buffer: *mut u8) -> Status,
 
     // Event & timer functions
-    create_event: unsafe extern "win64" fn(
+    create_event: unsafe extern "efiapi" fn(
         ty: EventType,
         notify_tpl: Tpl,
         notify_func: Option<EventNotifyFn>,
@@ -49,7 +49,7 @@ pub struct BootServices {
         event: *mut Event,
     ) -> Status,
     set_timer: usize,
-    wait_for_event: unsafe extern "win64" fn(
+    wait_for_event: unsafe extern "efiapi" fn(
         number_of_events: usize,
         events: *mut Event,
         out_index: *mut usize,
@@ -63,10 +63,10 @@ pub struct BootServices {
     reinstall_protocol_interface: usize,
     uninstall_protocol_interface: usize,
     handle_protocol:
-        extern "win64" fn(handle: Handle, proto: &Guid, out_proto: &mut *mut c_void) -> Status,
+        extern "efiapi" fn(handle: Handle, proto: &Guid, out_proto: &mut *mut c_void) -> Status,
     _reserved: usize,
     register_protocol_notify: usize,
-    locate_handle: unsafe extern "win64" fn(
+    locate_handle: unsafe extern "efiapi" fn(
         search_ty: i32,
         proto: *const Guid,
         key: *mut c_void,
@@ -82,12 +82,12 @@ pub struct BootServices {
     exit: usize,
     unload_image: usize,
     exit_boot_services:
-        unsafe extern "win64" fn(image_handle: Handle, map_key: MemoryMapKey) -> Status,
+        unsafe extern "efiapi" fn(image_handle: Handle, map_key: MemoryMapKey) -> Status,
 
     // Misc services
     get_next_monotonic_count: usize,
-    stall: extern "win64" fn(microseconds: usize) -> Status,
-    set_watchdog_timer: unsafe extern "win64" fn(
+    stall: extern "efiapi" fn(microseconds: usize) -> Status,
+    set_watchdog_timer: unsafe extern "efiapi" fn(
         timeout: usize,
         watchdog_code: u64,
         data_size: usize,
@@ -106,7 +106,7 @@ pub struct BootServices {
     // Library services
     protocols_per_handle: usize,
     locate_handle_buffer: usize,
-    locate_protocol: extern "win64" fn(
+    locate_protocol: extern "efiapi" fn(
         proto: &Guid,
         registration: *mut c_void,
         out_proto: &mut *mut c_void,
@@ -118,8 +118,8 @@ pub struct BootServices {
     calculate_crc32: usize,
 
     // Misc services
-    copy_mem: unsafe extern "win64" fn(dest: *mut u8, src: *const u8, len: usize),
-    set_mem: unsafe extern "win64" fn(buffer: *mut u8, len: usize, value: u8),
+    copy_mem: unsafe extern "efiapi" fn(dest: *mut u8, src: *const u8, len: usize),
+    set_mem: unsafe extern "efiapi" fn(buffer: *mut u8, len: usize, value: u8),
 
     // New event functions (UEFI 2.0 or newer)
     create_event_ex: usize,
@@ -272,7 +272,7 @@ impl BootServices {
         let mut event = MaybeUninit::<Event>::uninit();
 
         // Use a trampoline to handle the impedance mismatch between Rust & C
-        unsafe extern "win64" fn notify_trampoline(e: Event, ctx: *mut c_void) {
+        unsafe extern "efiapi" fn notify_trampoline(e: Event, ctx: *mut c_void) {
             let notify_fn: fn(Event) = mem::transmute(ctx);
             notify_fn(e); // SAFETY: Aborting panics are assumed here
         }
@@ -789,4 +789,4 @@ bitflags! {
 }
 
 /// Raw event notification function
-type EventNotifyFn = unsafe extern "win64" fn(event: Event, context: *mut c_void);
+type EventNotifyFn = unsafe extern "efiapi" fn(event: Event, context: *mut c_void);
diff --git a/src/table/runtime.rs b/src/table/runtime.rs
index 09d7cfeb8..b4aecb685 100644
--- a/src/table/runtime.rs
+++ b/src/table/runtime.rs
@@ -14,11 +14,11 @@ use core::ptr;
 pub struct RuntimeServices {
     header: Header,
     get_time:
-        unsafe extern "win64" fn(time: *mut Time, capabilities: *mut TimeCapabilities) -> Status,
-    set_time: unsafe extern "win64" fn(time: &Time) -> Status,
+        unsafe extern "efiapi" fn(time: *mut Time, capabilities: *mut TimeCapabilities) -> Status,
+    set_time: unsafe extern "efiapi" fn(time: &Time) -> Status,
     // Skip some useless functions.
     _pad: [usize; 8],
-    reset: unsafe extern "win64" fn(
+    reset: unsafe extern "efiapi" fn(
         rt: ResetType,
         status: Status,
         data_size: usize,
diff --git a/uefi-macros/src/lib.rs b/uefi-macros/src/lib.rs
index 909b54255..d3d8d910e 100644
--- a/uefi-macros/src/lib.rs
+++ b/uefi-macros/src/lib.rs
@@ -139,9 +139,9 @@ pub fn entry(args: TokenStream, input: TokenStream) -> TokenStream {
     let entry_fn_ident = &f.sig.ident;
 
     let result = quote!(
-        static _UEFI_ENTRY_POINT_TYPE_CHECK: extern "win64" fn(uefi::Handle, uefi::table::SystemTable<uefi::table::Boot>) -> uefi::Status = #entry_fn_ident;
+        static _UEFI_ENTRY_POINT_TYPE_CHECK: extern "efiapi" fn(uefi::Handle, uefi::table::SystemTable<uefi::table::Boot>) -> uefi::Status = #entry_fn_ident;
         #[no_mangle]
-        pub extern "win64" #f
+        pub extern "efiapi" #f
     );
     result.into()
 }
diff --git a/uefi-test-runner/src/proto/pi/mp.rs b/uefi-test-runner/src/proto/pi/mp.rs
index 4d74ef4ce..34d8c4572 100644
--- a/uefi-test-runner/src/proto/pi/mp.rs
+++ b/uefi-test-runner/src/proto/pi/mp.rs
@@ -61,12 +61,12 @@ fn test_get_processor_info(mps: &MPServices) {
     mps.enable_disable_ap(1, true, None).unwrap().unwrap();
 }
 
-extern "win64" fn proc_increment_atomic(arg: *mut c_void) {
+extern "efiapi" fn proc_increment_atomic(arg: *mut c_void) {
     let counter: &AtomicUsize = unsafe { &*(arg as *const _) };
     counter.fetch_add(1, Ordering::Relaxed);
 }
 
-extern "win64" fn proc_wait_100ms(arg: *mut c_void) {
+extern "efiapi" fn proc_wait_100ms(arg: *mut c_void) {
     let bt: &BootServices = unsafe { &*(arg as *const _) };
     bt.stall(100_000);
 }